Tobacco product



United States Patent 3,380,457 TOBACCO PRODUCT Joseph N. Schumacher,Wilmer A. Rohde, and Donald L.

Roberts, Winston-Salem, N.C., assignors to R. J. Reynolds TobaccoCompany, Winston-Salem, N.C., a corporation of New Jersey No Drawing.Filed Aug. 2, 1965, Ser. No. 476,687 12 Claims. (Cl. 131-17) Thisinvention relates to a tobacco product and has for an object theprovision of a composition and process for improving the flavor andaroma of tobacco and tobacco smoke.

It is well known in the tobacco art that the flavor and aroma of thetobacco product and the smoke from the tobacco are very importantconsiderations in so far as the ultimate consumer is concerned.Considerable efforts are exerted by the manufacturers of tobaccoproducts to provide a product that will be acceptable to the consumer,particularly as regards flavor and aroma characteristics. It has beenthe common practice in the tobacco industry to prepare blends ofdomestic and oriental t0- baccos in order to provide smoking tobaccowhich has a pleasing flavor and aroma before and during smoking.However, such a procedure is costly and may at times become prohibitivein the event that certain types of tobacco may be in short supply.Accordingly, it is a further object of this invention to provide a newclass of additive materials which when applied to the tobacco productsimprove and enhance the flavor and aroma of these products and the smokeemitted therefrom thereby increasing or enhancing the pleasure and othervalues that may be derived by the consumer from the use of theseproducts.

A further object of this invention is the provision of a process forenhancing or otherwise improving the flavor, aroma and other qualitiesof certain domestic, oriental, reconstituted or synthetic tobaccos whichmay be deficient in said flavor or aroma or other qualities.

An additional object of this invention is to provide a process ofpreparing a smoking ,tobacco or product which when smoked has anenhanced flavor or aroma.

A still further object of this invention is the provision of smokingproducts, such as cigarettes, cigars or pipe tobacco, and a process forforming same whereby the flavor and aroma before and during smoking areimproved or enhanced.

Further and additional objects will appear from the followingdescription and the appended claims.

'In accordance with one embodiment of .this invention a tobacco productis provided which has been treated with a small amount of a compoundselected from the group of compounds having the formula Formula Iwherein R R and R are selected from the group consisting of hydrogen andalkyl groups, with at least one of such substituents being alkyl. Thus,the tobacco additives of the present invention are alkyl substituted,saturated or unsaturated 6 lactones. Preferably the alkyl radicalspresent in the tobacco additives are lower alkyl radicals of 1 to 6carbon atoms. Thus, the alkyl substituents can be, for example, methyl,ethyl, propyl, isopropyl, normal butyl, isobutyl, pentyl or hexyl.

The following specific examples illustrate the preparation andcharacteristics of representative tobacco additives of the presentinvention. It will be appreciated, however, that this invention is notlimited to the specific process 3,380,457 Patented Apr. 30, 1968 "Ice bywhich the compounds may be prepared. All temperatures are expressed indegrees centigrade.

Example I.Synthesis 0f 3-is0pr0pyl-fi-valerolactone (a) 3-z's0propylglutaric acid.-To a vigorously stirred solution of 94 grams ofu-cyanoacetamide in 700 milliliters of water at 15 C. were added 35grams of isobutyraldehyde and 10 grams of piperidine. Stirring wascontinued for 3 hours while the reaction mixture was kept between l015C. The reaction mixture was then placed in the freezer overnight (16hours). After allowing the solidly frozen reaction mixture to thaw thefine, white crystals were collected on a Buchner funnel, washed anddried to yield 81.8 grams (82% of theory), of the 0:,11-dicyano-fl-isopropyl glutaramide (M.P. 152l54). Without furtherpurification grams of this product was placed in a 1 liter round bottomflask equipped with a reflux condenser; 300 milliliters of concentratedhydrochloric acid was added and the solution was brought to gentlereflux temperature. After 6 hours refluxing another 25 milliliters ofhydrochloric acid was added and refluxing continued (another check after12 hours indicated the hydrochloric acid content was still high) for atotal of 29 hours. This hot solution was then poured into an evaporatingdish, where upon cooling a volume of light tan solids precipitated outof solution. The solids were filtered from the solution in a Buchnerfunnel and thoroughly washed with methylene chloride (they were mostlysoluble in this organic solvent). Extraction of the aqueous extractionsolution with methylene chloride furnished 19 grams of the ,B-isopropylglutaric acid, melting point 98-101". A further extraction of theaqueous reaction solution with methyl ethyl ketone provided another 33grams of the title compound; total 52 grams, 83% of theory. A 1 gramsample of the crude isopropyl glutaric acid was recrystallized from 10%hydrochloric acid to raise its melting point to 103104 [lit. 102].

(b) 3-is0pr0pyl-glutaric anhydride.-A 500 milliliter round bottom flaskwas equipped with reflux condenser and heating mantle. The flask wascharged with 49 grams of the crude 3-isopropyl gluartic acid and 50milliliters of acetic anhydride and brought to reflux temperature for 6hours. The refluxed solution was then transferred to a 25 O-milliliterflask equipped with a 15 centimeter Vigreaux column distilling head.After distilling oi the acetic acid at atmospheric pressure the systemwas brought under reduced pressure. After removal of the remainingacetic anhydride 44.3 grams of the title compound were collected;boiling point 122-126/750;t. A previous 2 gram fraction, collected atboiling point 117/ 750 was also the I i-isopropyl glutaric anhydride;total 46.3 grams, 98% yield.

(0) Ethyl hydrogen-.i-isopropyl glutarate.This compound was prepared inthe usual manner by alcoholysis of the anhydride. A 200 milliliter roundbottom flask was equipped with reflux condenser, drying tube, andcharged with 44.3 grams (0.284 mole) of the anhydride and 13.08 grams(0.284 mole) of anhydrous ethanol and brought to full reflux on thesteam bath for one hour and allowed to stand overnight (15 hours). Aninfrared spectrum of this faintly colored solution indicated that thehalf-ester was present in high percentage. This reaction mixture wasdistilled under vacuum and 3 fractions were collected after a forerun of1 milliliter of ethanol was distilled off. The tabulated data are below:

TABLE L-DISTILLATION OF ETHYLHYDROGEN-Zi-ISO- PROPYL GLUTARATE 3 4 1gram of yellow pot residue was discarded; 87% yield and Dalta, J. Chem.Soc., 3195 (1951), in 50 milliliters of the title compound. of 95%ethanol was added 15 grams of potassium boro- (d)dl-3-is0pr0pyl-6-valer0lactone.A 3-neck, 1 liter hydride in smallportions until the reaction ceased. The flask was set up on the steambath and equipped with solution was refluxed for one hour, cooled,acidified with reflux condenser, drying tube and mechanical stirrer (all5 sulfuric acid and extracted with ether. Concentraequipment thoroughlydried). The flask was charged with tion of the ether layer gave5-hydroxy-2-isopropyl- 300 milliliters of tetrahydrofuran that had beenfreshly hexanoic acid as an almost colorless oil. This hydroxy distilledfrom calcium hydride and 45.7 grams (0.226 acid was heated on an oilbath at 180 for one hour and mole) of ethylhydrogen-3-isopropylglutarate. To this distilled under reduced pressure; 7.2 grams ofS-hydroxyvigorously stirred solution was added 24.4 grams (0.4-5 102-isopropylhexanoic acid, fi-lactone, boiling oint 112- mole) ofpotassium borohydride followed by 11 grams l 15/8 millimeters, wereobtained. The lactone was of lithium chloride. This mixture was stirredat room identified from its infrared and nuclear magneticresontemperature for 0.5 hour before turning the steam into ancespectra.

the bath. Upon heating a vigorous reaction with evolution Example IV ofgas set in; the stirred mixture was kept at a gentle 15 reflux for 4.5hours. After cooling to room temperature fiy is a commcrclaltlyavallahlc the reaction was hydrolyzed in the usual manner withchfimiffll having formula dilute hydrochloric acid and thoroughlyextracted with (3H ether. After drying the ether solution the ether wasremoved by distillation over a steam bath and the residue wastransferred to a 100 milliliter distilling flask equipped with 15centimeter Vigreaux column and fraction col- 0 lecter for distillationunder reduced pressure. The results 0 are tabulated below: It is awater-White liquid, boiling point 100/ 10 milli- TABLE II.DISTILLATIONOF 3-Is0PROPYL-s-VALEROLACTONE Fraction Vapor Pressure Weight (g.)Product Temp. (deg.)

1 85-89 800 18. 4 3-is0propyl-a-valerolactone (IR). 2 90-105 800 2. 28Lactone+diol. 3 106 750 2. 55 3-isopropyl-1,5-pentanediol (IR).

1 A 7 gram residue of very viscous material was left in the distillingflask. It proved to be the diol contaminated with boric acid.

The tobacco additive dl-3-isopropyl-fi-valerolactone meters; infraredspertrum: 5:77 (vs), 7.95 (s), 8.15 (s), has the following structure:9.20 (s); nuclear magnetic resonance spectrum: 7:8.92

C and and and 5.74 [(2)-CH O--]; C H O mass=1l4.

It has been found that the tobacco additives of the invention whenincorporated into tobacco products impart a flavor and aroma both beforeand during smoking 0 0 which many smokers consider to be desirable insmoking It is a water-white liquid, boiling point 59/90,t, products.However, it is pointed out that the methods for 139/14 millimeters;infrared spectrum: 5.8 (vs), 7.95 fi g r characterizing the q y of aflavor 0r aroma (s), 8.2 (s) and 9.25 (vs) ,1.; nuclear magneticresonance in the tobacco art are almost purely subjective anddifferspectrum: ent smokers may define the same flavor quitedifferently. Also, the compounds included within the broad scope of908(6) (Spht 150p mp [(2) CH2 CO this invention may impart differentflavors or aromas deand 5.77 [('2)CH O-];C H O mass=142. pending uponthe alkyl substituents therein. Thus, the compounds comprehended by thisinvention, by subjective tests, impart characteristic flavors which aredesirable in tobacco products and the smoke therefrom even though To aSohlhoh 0f 1 g of fi'lsoplopyl'a'valerolactohe the exact characterthereof cannot be described on the ExampleII.5-hydroxy-3-is0propyl-2-penrenoic acid, 6-lactone p f lf f accordingto the method of Example in 10 basis of known standards. The tobaccoadditive of Exammllhhters 0f h h feh'achlorlde Weft? added grams pic Iimparts an :aroma and flavor which is reminiscent of of q and mhttureWas refluxed coconut which many smokers consider to be desirable in ahours hhdfir Irradlahon Wlth all Infrared heat P- tobacco product. Thetobacco additive of Example II im- Filtration of the solution followedby concentration gave parts an aroma and flavor Which some characterizeas a residue which was heated in an oil bath with 5 milliliters Coconut;the tobacco additive of Example III has a Spicy of dimethylaniline atfor one hour. The solution was note; and that f Example IV has a spicyapple w diluted with 25 milliliters of water, extracted with ether, Inaccordance with this invention a compound and the ether lhyer W WashedWith 100 milliliters of braced by generic formula I, or mixturesthereof, is added 5 N hydrochlorlc acld h concentfated- Vapor Phase 60to tobacco or applied to a smoking article or its compochfhmatogl'aphy0f the resldue gave mainly one subs/range nent parts in amounts of about0.01 to 2.0 percent by Whlch Was Shown y Infrared and nuclear maghehcweight of the product. Preferably the amount of additive resonance p pyto have The formula: is between about 0.1 and 0.5 percent by weight inorder to H provide a tobacco product having a desired flavor and Jaroma. However, the amount used will depend up n the amount of flavorand aroma desired and the particular compound or mixture thereof that isused. The additive may be incorporated at any step in the treatment ofthe O O tobacco but is preferably added after raging, curing andshredding and before the tobacco is formed into cigarettes.

Example y y' p y acid, Likewise, it will be apparent that only a portionof the Haclohe tobacco need be treated and the thus treated tobacco mayTo a l i of 163 grams f 5.k t 2.is0pr0py1- be blended with othertobaccos before the cigarettes or hexanoic acid, prepared by the methodof Bardhan, De, other smoking articles are formed. In such case the t0-bacco treated may have the additive in excess of the amounts aboveindicated so that when blended with other tobaccos the final productwill have the percentage within the indicated range.

In accordance with one specific embodiment of this invention, an aged,flue-cured and shredded tobacco is sprayed with a 1% ethyl alcoholsolution of 3-isopropyl- B-valerolactone in an amount to provide atobacco containing 0.2 percent by weight of the additive on a dry basis.Thereafter the alcohol is removed by evaporation and the tobacco ismanufactured into cigarettes by the usual techniques. It has been foundthat the cigarette when prepared as indicated has a desired and pleasingflavor, an aroma which to some people is reminiscent of coconut and isdetectable and pleasing in the main and side smoke streams when thecigarette is smoked.

'I he additives falling within the scope of this invention may beapplied to the tobacco by spraying, dipping or otherwise, utilizingsuitable suspensions or solutions of the additive. 'I'hus water orvolatile organic solvents, such as alcohol, ether, acetone, volatilehydrocarbons and the like, may be used as the carrying medium for theadditive while it is being applied to the tobacco. Also, other flavorandaroma-producing additives, such as those disclosed in United StatesPatents Nos. 2,766,145, 2,905,575, 2,905,- 576, 2,978,365 and 3,041,211may be incorporated into the tobacco with the additive of thisinvention.

While this invention is principally useful in the manufacture ofcigarette tobacco, it is also suitable for use in connection with themanufacture of pipe tobacco, cigars or other tobacco products.Furthermore, the compounds may be added to certain tobacco substitutesof natural or synthetic origin and by the term tobacco as usedthroughout this specification is meant anv composition intended forhuman consumption by smoking or otherwise, whether composed of tobaccoplant parts or substitute materials or both.

Also, the invention has been particularly described with reference tothe addition of the compounds directly to tobacco. However, it will beapparent that the compound may be applied to the paper of the cigaretteor to the wrapper of a cigar. Also it may be incorporated into thefilter tip, the packaging material or the seam paste employed for gluingthe cigarette paper. Thus a tobacco product is provided which includesthe specified additives and tobacco although in every instance thecompound need not be admixed with the tobacco as above specificallydescribed.

While several particular embodiments of this invention are shown above,it will be understood, of course, that the invention is not to belimited thereto, since many modifications may be made, and it iscontemplated, therefore, by the appended claims, to cover any suchmodifications as fall within the true spirit and scope of thisinvention.

We claim:

1. A tobacco product having added thereto an amount suflicient to alterthe flavor or aroma of the tobacco product of a compound selected fromthe group of compounds having the formula Formula I wherein R R and Rare selected from the group consisting of hydrogen and alkyl groups withat least one of such substituents being alkyl.

2. A tobacco product having added thereto an amount sutficient to alterthe flavor or aroma of the tobacco product of a compound selected fromthe group of compounds having the formula Formula persed therein a smallamount sufiicient to improve the flavor thereof of3-isopropyl-fi-valerolactone.

6. A tobacco product having added thereto and dispersed therein a smallamount suflicient to improve the flavor thereof of5-hydroxy-3-isopropyl-2-pentenoic acidfi-lactone.

7. A tobacco product having added thereto and dispersed therein a smallamount suflicient to improve the flavor thereof ofS-methyl-fi-valerolactone.

8. A tobacco product having added thereto and dispersed therein a smallamount suflicient to improve the flavor thereof of5-hydr0xy-2-isopropylhexanoic acid.

9. The product recited in claim 5 wherein the amount of flavorant isbetween about 0.01 and 2.0 percent by weight of said product.

10. The product recited in claim 6 wherein the amount of flavorant isbetween about 0.01 and 2.0 percent by weight of said product.

11. The product recited in claim 7 wherein the amount of flavorant isbetween about 0.01 and 2.0 percent by weight of said product.

12. The product recited in claim 8 wherein the amount of flavorant isbetween about 0.01 and 2.0 percent by weight of said product.

References Cited UNITED STATES PATENTS 2,766,149 10/1956 Rowland 131172,766,150 lO/1956 Teague 'l31-17 SAMUEL KOREN, Primary Examiner.

D. I DONOHUE, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,380,457 April 30 1968 Joseph N. Schumacher et a1.

It is certified that error appears in the above identified patent andthat said Letters Patent are hereby corrected as show below:

Columns 3 and 4, TfBLE II, fourth column, line 3,

"2 .55" should read 2 ,55 Column 4 line 16 I'chemiral" should readchemical liI 1e 32,

'spertrum: 5 77" should read spectrum: 5.77

Column 6, line 14, "Formula" should read Formula I Signed and sealedthis 7th day of October 1969.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR.

1. A TOBACCO PRODUCT HAVING ADDED THERETO AN AMOUNT SUFFICIENT TO ALTERTHE FLAVOR OR AROMA OF THE TOBACCO PRODUCT OF A COMPOUND SELECTED FROMTHE GROUP OF COMPOUNDS HAVING THE FORMULA